The world population of non religious** ranges anywhere from 850 million to 1.1 billion making up 15 to 26.8%.

The US population of non religious** ranges anywhere from 25 to 30 million making up 9 to 15%.

If the US Prison Population statistics are accurate then there are far less nonbelievers in the prison system. This can be interpreted in many ways. Note that religious conversion is very active in prisons.

** the ambiguous term non religious as used above includes those identified as atheist, agnostic, secular, nonbeliever and non-religious as defined by those responsible for the polls and statistics.

Top 10 Countries
With Highest Percentage of Atheists (1991)

Divorce rates by religion (U.S.)

Religion

% have been
divorced

Jews

30%

Born-again Christians

27%

Other Christians

24%

Atheists, Agnostics

21%

The Associated Press computed divorce statistics from data supplied
by the U.S. Census Bureau and the National Center for Health. They showed that
the highest divorce rates were found in the 'Bible Belt'. "Tennessee,
Arkansas, Alabama and Oklahoma round out the Top Five in frequency of divorce...the
divorce rates in these conservative states are roughly 50 percent above the
national average" of 4.2/1000 people.